Palladium-catalyzed intramolecular aerobic C-H amination of enamines for the synthesis of 2-trifluoromethylindoles

A new palladium-catalyzed C-H amination of aryl enamines for the synthesis of trifluoromethylated indoles is established. The attractive features of this transformation are the use of atom-economical O2 as the oxidant and easily prepared enamines as substrates. A variety of pharmaceutically important 2-trifluoromethyl indoles can be targeted in moderate to good yields with good functional compatibility.